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@random That question only covers the general area of posting answers as comments. It doesn't cover either of the example case I provided nor the follow-on questions "Is it encouraged or discouraged? Would it be ethical to re-post it as an answer with reference to the original commenter?"
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marcogDec 20 '10 at 15:21

You might be able to open the subquestions as a new question, reference the ones marked as "duplicates" and explain why they are not sufficient to answer the new question. I don't know if those would be closed too, but it's worth a shot.
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Mark RansomDec 20 '10 at 15:49